[Effects of apomorphine and haloperidol on experimental hepatocarcinogenesis]

The modifying effect of apomorphine and haloperidol - agonist and antagonist of dopamine receptors, respectively - on the development of N-nitrosodiethylamine (NDEA) - induced hepatic tumors was studied in 60 noninbred albino male rats. The study was concerned with an evaluation of the effect of the drugs on tumor frequency as well as on the neoplastic transformation of such cell elements as hepatocytes, cholangiolar epithelium and endothelium. It was found that apomorphine significantly inhibited the carcinogenic effect of NDEA and neoplastic transformation of hepatocytes. Haloperidol revealed a tendency of stimulating NDEA effect on cholangiolar epithelium. The results are discussed in the context of the considerable importance of the functional condition of the presynaptic receptors of catecholaminergic systems in the mechanism of carcinogenic chemical action.